Now I have figured out how to allow you, the viewer, to view my 3D viewable models in a Google Cardboard viewer!
Here's an example, but the general idea is that if you stick "/embed?cardboard=1" (without the quotes) after the model URL you will get a stereo viewable image for your Google Cardboard-compatible viewer.
Tap the image on your phone and put it in a Google Cardboard viewer.
I have one that I put together for under $8 (half of which was shipping). The Vel-cro was stronger than the Cardboard's cardboard, and it tore but still works, and the images look awesome.
I have now ordered a View-Master VR Viewer, usually $29.99, I got one for $21 (post-Xmas discount) and it should arrive in a couple of days. I'll let you know how that goes.